userdoc.texi

gcc-2.95.3 Linux下最常用的C编译器

window is separated from the next by its modeline.  At any time, there
is only one @dfn{active} window, that is, the window in which the cursor
appears.  There are commands available for creating windows, changing
the size of windows, selecting which window is active, and for deleting
windows.

@menu
* The Mode Line::       What appears in the mode line?
* Basic Windows::       Manipulating windows in Info.
* The Echo Area::       Used for displaying errors and reading input.
@end menu

@node The Mode Line
@section The Mode Line

A @dfn{mode line} is a line of inverse video which appears at the bottom
of an info window.  It describes the contents of the window just above
it; this information includes the name of the file and node appearing in
that window, the number of screen lines it takes to display the node,
and the percentage of text that is above the top of the window.  It can
also tell you if the indirect tags table for this info file needs to be
updated, and whether or not the info file was compressed when stored on
disk.

Here is a sample mode line for a window containing an uncompressed file
named @file{dir}, showing the node @samp{Top}.

@example
-----Info: (dir)Top, 40 lines --Top---------------------------------------
            ^^   ^   ^^^        ^^
          (file)Node #lines    where
@end example

When a node comes from a file which is compressed on disk, this is
indicated in the mode line with two small @samp{z}'s.  In addition, if
the info file containing the node has been split into subfiles, the name
of the subfile containing the node appears in the modeline as well:

@example
--zz-Info: (emacs)Top, 291 lines --Top-- Subfile: emacs-1.Z---------------
@end example 

When Info makes a node internally, such that there is no corresponding
info file on disk, the name of the node is surrounded by asterisks
(@samp{*}).  The name itself tells you what the contents of the window
are; the sample mode line below shows an internally constructed node
showing possible completions:

@example
-----Info: *Completions*, 7 lines --All-----------------------------------
@end example

@node Basic Windows
@section Window Commands

It can be convenient to view more than one node at a time.  To allow
this, Info can display more than one @dfn{window}.  Each window has its
own mode line (@pxref{The Mode Line}) and history of nodes viewed in that
window (@pxref{Node Commands, , @code{history-node}}).

@table @asis
@item @code{C-x o} (@code{next-window})
@cindex windows, selecting
@kindex C-x o
@findex next-window
Selects the next window on the screen.  Note that the echo area can only be
selected if it is already in use, and you have left it temporarily.
Normally, @samp{C-x o} simply moves the cursor into the next window on
the screen, or if you are already within the last window, into the first
window on the screen.  Given a numeric argument, @samp{C-x o} moves over
that many windows.  A negative argument causes @samp{C-x o} to select
the previous window on the screen.

@item @code{M-x prev-window}
@findex prev-window
Selects the previous window on the screen.  This is identical to
@samp{C-x o} with a negative argument.

@item @code{C-x 2} (@code{split-window})
@cindex windows, creating
@kindex C-x 2
@findex split-window
Splits the current window into two windows, both showing the same node.
Each window is one half the size of the original window, and the cursor
remains in the original window.  The variable @code{automatic-tiling}
can cause all of the windows on the screen to be resized for you
automatically, please @pxref{Variables, , automatic-tiling} for more
information.

@item @code{C-x 0} (@code{delete-window})
@cindex windows, deleting
@kindex C-x 0
@findex delete-window
Deletes the current window from the screen.  If you have made too many
windows and your screen appears cluttered, this is the way to get rid of
some of them.

@item @code{C-x 1} (@code{keep-one-window})
@kindex C-x 1
@findex keep-one-window
Deletes all of the windows excepting the current one.

@item @code{ESC C-v} (@code{scroll-other-window})
@kindex ESC C-v, in Info windows
@findex scroll-other-window
Scrolls the other window, in the same fashion that @samp{C-v} might
scroll the current window.  Given a negative argument, the "other"
window is scrolled backward.

@item @code{C-x ^} (@code{grow-window})
@kindex C-x ^
@findex grow-window
Grows (or shrinks) the current window.  Given a numeric argument, grows
the current window that many lines; with a negative numeric argument,
the window is shrunk instead.

@item @code{C-x t} (@code{tile-windows})
@cindex tiling
@kindex C-x t
@findex tile-windows
Divides the available screen space among all of the visible windows.
Each window is given an equal portion of the screen in which to display
its contents.  The variable @code{automatic-tiling} can cause
@code{tile-windows} to be called when a window is created or deleted.
@xref{Variables, , @code{automatic-tiling}}.
@end table

@node The Echo Area
@section The Echo Area
@cindex echo area

The @dfn{echo area} is a one line window which appears at the bottom of
the screen.  It is used to display informative or error messages, and to
read lines of input from you when that is necessary.  Almost all of the
commands available in the echo area are identical to their Emacs
counterparts, so please refer to that documentation for greater depth of
discussion on the concepts of editing a line of text.  The following
table briefly lists the commands that are available while input is being
read in the echo area:

@table @asis
@item @code{C-f} (@code{echo-area-forward})
@kindex C-f, in the echo area
@findex echo-area-forward
Moves forward a character.

@item @code{C-b} (@code{echo-area-backward})
@kindex C-b, in the echo area
@findex echo-area-backward
Moves backward a character.

@item @code{C-a} (@code{echo-area-beg-of-line})
@kindex C-a, in the echo area
@findex echo-area-beg-of-line
Moves to the start of the input line.

@item @code{C-e} (@code{echo-area-end-of-line})
@kindex C-e, in the echo area
@findex echo-area-end-of-line
Moves to the end of the input line.

@item @code{M-f} (@code{echo-area-forward-word})
@kindex M-f, in the echo area
@findex echo-area-forward-word
Moves forward a word.

@item @code{M-b} (@code{echo-area-backward-word})
@kindex M-b, in the echo area
@findex echo-area-backward-word
Moves backward a word.

@item @code{C-d} (@code{echo-area-delete})
@kindex C-d, in the echo area
@findex echo-area-delete
Deletes the character under the cursor.

@item @code{DEL} (@code{echo-area-rubout})
@kindex DEL, in the echo area
@findex echo-area-rubout
Deletes the character behind the cursor.

@item @code{C-g} (@code{echo-area-abort})
@kindex C-g, in the echo area
@findex echo-area-abort
Cancels or quits the current operation.  If completion is being read,
@samp{C-g} discards the text of the input line which does not match any
completion.  If the input line is empty, @samp{C-g} aborts the calling
function.

@item @code{RET} (@code{echo-area-newline})
@kindex RET, in the echo area
@findex echo-area-newline
Accepts (or forces completion of) the current input line.

@item @code{C-q} (@code{echo-area-quoted-insert})
@kindex C-q, in the echo area
@findex echo-area-quoted-insert
Inserts the next character verbatim.  This is how you can insert control
characters into a search string, for example.

@item @var{printing character} (@code{echo-area-insert})
@kindex printing characters, in the echo area
@findex echo-area-insert
Inserts the character.

@item @code{M-TAB} (@code{echo-area-tab-insert})
@kindex M-TAB, in the echo area
@findex echo-area-tab-insert
Inserts a TAB character.

@item @code{C-t} (@code{echo-area-transpose-chars})
@kindex C-t, in the echo area
@findex echo-area-transpose-chars
Transposes the characters at the cursor.
@end table

The next group of commands deal with @dfn{killing}, and @dfn{yanking}
text.  For an in depth discussion of killing and yanking,
@pxref{Killing, , Killing and Deleting, emacs, the GNU Emacs Manual}

@table @asis
@item @code{M-d} (@code{echo-area-kill-word})
@kindex M-d, in the echo area
@findex echo-area-kill-word
Kills the word following the cursor.

@item @code{M-DEL} (@code{echo-area-backward-kill-word})
@kindex M-DEL, in the echo area
@findex echo-area-backward-kill-word
Kills the word preceding the cursor.

@item @code{C-k} (@code{echo-area-kill-line})
@kindex C-k, in the echo area
@findex echo-area-kill-line
Kills the text from the cursor to the end of the line.

@item @code{C-x DEL} (@code{echo-area-backward-kill-line})
@kindex C-x DEL, in the echo area
@findex echo-area-backward-kill-line
Kills the text from the cursor to the beginning of the line.

@item @code{C-y} (@code{echo-area-yank})
@kindex C-y, in the echo area
@findex echo-area-yank
Yanks back the contents of the last kill.

@item @code{M-y} (@code{echo-area-yank-pop})
@kindex M-y, in the echo area
@findex echo-area-yank-pop
Yanks back a previous kill, removing the last yanked text first.
@end table

Sometimes when reading input in the echo area, the command that needed
input will only accept one of a list of several choices.  The choices
represent the @dfn{possible completions}, and you must respond with one
of them.  Since there are a limited number of responses you can make,
Info allows you to abbreviate what you type, only typing as much of the
response as is necessary to uniquely identify it.  In addition, you can
request Info to fill in as much of the response as is possible; this
is called @dfn{completion}.

The following commands are available when completing in the echo area:

@table @asis
@item @code{TAB} (@code{echo-area-complete})
@itemx @code{SPC}
@kindex TAB, in the echo area
@kindex SPC, in the echo area
@findex echo-area-complete
Inserts as much of a completion as is possible.

@item @code{?} (@code{echo-area-possible-completions})
@kindex ?, in the echo area
@findex echo-area-possible-completions
Displays a window containing a list of the possible completions of what
you have typed so far.  For example, if the available choices are:
@example
bar
foliate
food
forget
@end example
and you have typed an @samp{f}, followed by @samp{?}, the possible
completions would contain:
@example
foliate
food
forget
@end example
i.e., all of the choices which begin with @samp{f}.  Pressing @key{SPC}
or @key{TAB} would result in @samp{fo} appearing in the echo area, since
all of the choices which begin with @samp{f} continue with @samp{o}.
Now, typing @samp{l} followed by @samp{TAB} results in @samp{foliate}
appearing in the echo area, since that is the only choice which begins
with @samp{fol}.

@item @code{ESC C-v} (@code{echo-area-scroll-completions-window})
@kindex ESC C-v, in the echo area
@findex echo-area-scroll-completions-window
Scrolls the completions window, if that is visible, or the "other"
window if not.
@end table

@node Printing Nodes
@chapter Printing Out Nodes
@cindex printing

You may wish to print out the contents of a node as  a quick reference
document for later use.  Info provides you with a command for doing
this.  In general, we recommend that you use @TeX{} to format the
document and print sections of it, by running @code{tex} on the texinfo
source file.

@table @asis
@item @code{M-x print-node}
@findex print-node
@cindex INFO_PRINT_COMMAND, environment variable
Pipes the contents of the current node through the command in the